1. Field of the Invention
The present invention generally relates to rope chain jewelry, particularly to spiral diamond cut rope chains and apparatus and methods for cutting thereof.
2. Description of the Related Art
Rope chain jewelry is a chain in the form of a rope constituted by a helical series of open rings or links that are interlinked with one another to define a configuration similar to a continuous double-stranded rope. Rope chains made of solid rings are simply known as rope chains while those made of hollow rings or links are known as "hollow rope chains".
The present invention is directed specifically to a type of rope chain to be known as a "spiral diamond cut rope chain" which derives from, but provides a look which differs from, the conventional "diamond cut rope chain", discussed below.
Apparatus and methods for fabricating rope chains are known in the prior art as exemplified by U.S. Pat. No. 5,115,959 to Weinberg et al. which is directed to an automatic soldering machine for soldering a rope chain. Weinberg et al., discloses a machine having a pair of gears, each with a peripheral surface defining a trench for engaging one of the strands of a rope chain to feed and place successive link junctions of the rope chain relative to a series of hollow soldering needles.
A detailed discussion of a method for making a conventional diamond cut rope chain is provided in U.S. Pat. No. 5,125,225 to Strobel which discloses a process for making a hollow diamond cut rope chain. The Strobel patent also describes common problems inherent in fabricating a hollow diamond cut rope chain. For example, to achieve a square or hexagonal cross-section chain, the depth of the diamond cut must be greater than the outer shell thickness of the link of which a hollow rope chain is to be made. If one were to attempt to precut each link before assembly, the resulting links would be differently sheared or deformed making it impossible to assemble them into a completed rope chain having the conventional diamond cut.
As disclosed in the Strobel patent, a diamond cut rope chain is a type of chain in which the links of the chain are given a certain degree of shine and/or sparkle by shaving off or shearing away flat sections (also called facets) from the outer surface of the solid toroidal-shaped links, leaving relatively flat surfaces for light to reflect therefrom. Diamond cutting of solid link rope chains is done with a non-rotating, sharp diamond blade capable of creating a deep cut into the outer surface of the rope chain by scraping away sections from the outer surfaces of the rope chain which is tightly wound on a rotatable lathe drum.
U.S. Pat. No. 5,285,625 to Ofrat et al. discloses a rope chain with diamond cut facets which extend spirally around the longitudinal center of the chain. The chain can be formed of solid or hollow links. The Ofrat et at. patent attempts to provide a spiral diamond cut rope chain having a flattened or decorated outer surface. Diamond cut facets are formed on the links of the chain in a path that extends helically around the chain by faceting each of the individual links at one or more locations thereon. The Ofrat et al. patent is also directed to a process of forming diamond cut faceting in the individual hollow or solid links of an assembled jewelry rope chain.
Specifically, Ofrat et al. disclose an apparatus for applying a shearing force to the rope chain on diametrically opposed sides thereof and on the individual links that are in that instant at a predetermined holding position adjacent the cut forming tools. The shearing force applied to the links results in a scraping away of sections from the outer surfaces of the links. Such scraping and shearing force on the chain links is affected by the friction, contour, and geometry of the surface being cut, which in the case of a series of links present in a rope chain results in an overall uneven cut of the chain facet being formed.
None of the prior art apparatus and methods for cutting a rope chain teach a cutting force that is a controlled rotational cutting force, to create a cut surface that is smooth and even, such that the cut surfaces of the links exhibit much greater shine and reflectivity to make the rope chain more desirable to consumers.
Therefore, the need arises for a spiral diamond cut jewelry rope chain that has a smooth, consistent, and even spiral faceted outer surface and method for fabricating the same. Such a rope chain should have a high quality shine and reflectivity so as to be highly desirable and attractive to consumers.